1. Field of the Invention
The present invention relates to a coating apparatus for coating a web of paper.
More specifically, the present invention relates to a coating apparatus which permits the selective coating of one or both sides of a web of paper.
2. Information Disclosure Statement
Coaters have been known for applying coating material to backing rolls such that the coating material is transferred to coating rolls for simultaneously applying coating to both sides of a web.
However, in specialty mills, various grades of paper must be coated on a short run basis, and it is desirable to have a coating apparatus having the flexibility to rapidly change from coating one grade to another.
The present invention provides a coating machine with the flexibility to apply coating material simultaneously to both sides of a web by the roll method or to the first or second side of the web by a single blade coating arrangement.
Some of the advantages achieved by the aforementioned arrangement are the provision of a single tension control system. Also, with the arrangement according to the present invention, there is no requirement to make roll changes for a particular web path or coating method.
Additional advantages of the arrangement according to the present invention include:
1. Alternate pathways through the coater do not require reversible drives for the paper rolls common to alternate web runs. PA1 2. The paper web rolls do not need to be movable in order to accommodate alternate run geometries. PA1 3. Each of the web runs in the alternate coating modes do not require a separate dedicated tension control loop. PA1 4. Each of the alternate web runs does not necessarily require a dedicated drying section. Rather, the drying arrangement may be usable for more than one web run. PA1 5. The hardness of the respective rolls does not have to be changed for the handling of various web grades.
Additionally, the arrangement according to the present invention provides a coating apparatus in which the drying means is located above the coating apparatus, thereby enhancing accessibility to the coater apparatus and, particularly, permits access to the short dwell coater heads thereof.
Therefore, it is a primary objective of the present invention to provide a coating apparatus which permits alternate runs of the web therethrough for accomplishing various coating operations.
A further object of the present invention is to provide a coating apparatus having improved accessibility.
Other objects and advantages of the present invention will be readily apparent to those skilled in the art by a consideration of the detailed description contained hereinafter, taken in conjunction with the annexed drawings.